This invention relates generally to shoe-making injection molding machines, and more specifically, it concerns with improvements in and relating to the shoe core or last supporting structure of such machines.
Such shoe-making injection molding machine is so designed and arranged as for molding a sole and attaching same to a prefabricated instep. Several similar molding steps are generally performed simultaneously or in an successive order one after another and on the same machine fitted with a plurality of the heads and the corresponding sole mold assemblies.
Much difficulties have been encountered with use of the above kind conventional machine on account of several main machine parts becoming hot during repeated and extended molding operations, resulting in localized thermal expansion of these parts distrubing especially smooth sliding and rotary movements of the relatively movable parts and substantial deterioration of the oil supplied thereto for optimum lubrication.
The main object of the present invention is, therefore, to provide an improved shoe-making injection molding machine wherein adversely affecting heat transfer from the sole mold assembly or assemblies to other main working parts of the machine is substantially reduced.